1 | /* |
2 | * Copyright 2019 Google LLC |
3 | * |
4 | * Use of this source code is governed by a BSD-style license that can be |
5 | * found in the LICENSE file. |
6 | */ |
7 | |
8 | #ifndef SkResources_DEFINED |
9 | #define SkResources_DEFINED |
10 | |
11 | #include "include/core/SkData.h" |
12 | #include "include/core/SkRefCnt.h" |
13 | #include "include/core/SkString.h" |
14 | #include "include/core/SkTypes.h" |
15 | #include "include/private/SkMutex.h" |
16 | #include "include/private/SkTHash.h" |
17 | |
18 | #include <memory> |
19 | |
20 | class SkAnimCodecPlayer; |
21 | class SkImage; |
22 | |
23 | namespace skresources { |
24 | |
25 | /** |
26 | * Image asset proxy interface. |
27 | */ |
28 | class SK_API ImageAsset : public SkRefCnt { |
29 | public: |
30 | /** |
31 | * Returns true if the image asset is animated. |
32 | */ |
33 | virtual bool isMultiFrame() = 0; |
34 | |
35 | /** |
36 | * Returns the SkImage for a given frame. |
37 | * |
38 | * If the image asset is static, getImage() is only called once, at animation load time. |
39 | * Otherwise, this gets invoked every time the animation time is adjusted (on every seek). |
40 | * |
41 | * Embedders should cache and serve the same SkImage whenever possible, for efficiency. |
42 | * |
43 | * @param t Frame time code, in seconds, relative to the image layer timeline origin |
44 | * (in-point). |
45 | */ |
46 | virtual sk_sp<SkImage> getFrame(float t) = 0; |
47 | }; |
48 | |
49 | class MultiFrameImageAsset final : public ImageAsset { |
50 | public: |
51 | /** |
52 | * By default, images are decoded on-the-fly, at rasterization time. |
53 | * Large images may cause jank as decoding is expensive (and can thrash internal caches). |
54 | * |
55 | * Pass |predecode| true to force-decode all images upfront, at the cost of potentially more RAM |
56 | * and slower animation build times. |
57 | */ |
58 | static sk_sp<MultiFrameImageAsset> Make(sk_sp<SkData>, bool predecode = false); |
59 | |
60 | bool isMultiFrame() override; |
61 | |
62 | sk_sp<SkImage> getFrame(float t) override; |
63 | |
64 | private: |
65 | explicit MultiFrameImageAsset(std::unique_ptr<SkAnimCodecPlayer>, bool predecode); |
66 | |
67 | std::unique_ptr<SkAnimCodecPlayer> fPlayer; |
68 | bool fPreDecode; |
69 | |
70 | using INHERITED = ImageAsset; |
71 | }; |
72 | |
73 | /** |
74 | * ResourceProvider is an interface that lets rich-content modules defer loading of external |
75 | * resources (images, fonts, etc.) to embedding clients. |
76 | */ |
77 | class SK_API ResourceProvider : public SkRefCnt { |
78 | public: |
79 | /** |
80 | * Load a generic resource (currently only nested animations) specified by |path| + |name|, |
81 | * and return as an SkData. |
82 | */ |
83 | virtual sk_sp<SkData> load(const char[] /* resource_path */, |
84 | const char[] /* resource_name */) const { |
85 | return nullptr; |
86 | } |
87 | |
88 | /** |
89 | * Load an image asset specified by |path| + |name|, and returns the corresponding |
90 | * ImageAsset proxy. |
91 | */ |
92 | virtual sk_sp<ImageAsset> loadImageAsset(const char[] /* resource_path */, |
93 | const char[] /* resource_name */, |
94 | const char[] /* resource_id */) const { |
95 | return nullptr; |
96 | } |
97 | |
98 | /** |
99 | * Load an external font and return as SkData. |
100 | * |
101 | * @param name font name ("fName" Lottie property) |
102 | * @param url web font URL ("fPath" Lottie property) |
103 | * |
104 | * -- Note -- |
105 | * |
106 | * This mechanism assumes monolithic fonts (single data blob). Some web font providers may |
107 | * serve multiple font blobs, segmented for various unicode ranges, depending on user agent |
108 | * capabilities (woff, woff2). In that case, the embedder would need to advertise no user |
109 | * agent capabilities when fetching the URL, in order to receive full font data. |
110 | */ |
111 | virtual sk_sp<SkData> loadFont(const char[] /* name */, |
112 | const char[] /* url */) const { |
113 | return nullptr; |
114 | } |
115 | }; |
116 | |
117 | class FileResourceProvider final : public ResourceProvider { |
118 | public: |
119 | static sk_sp<FileResourceProvider> Make(SkString base_dir, bool predecode = false); |
120 | |
121 | sk_sp<SkData> load(const char resource_path[], const char resource_name[]) const override; |
122 | |
123 | sk_sp<ImageAsset> loadImageAsset(const char[], const char[], const char[]) const override; |
124 | |
125 | private: |
126 | FileResourceProvider(SkString, bool); |
127 | |
128 | const SkString fDir; |
129 | const bool fPredecode; |
130 | |
131 | using INHERITED = ResourceProvider; |
132 | }; |
133 | |
134 | class ResourceProviderProxyBase : public ResourceProvider { |
135 | protected: |
136 | explicit ResourceProviderProxyBase(sk_sp<ResourceProvider>); |
137 | |
138 | sk_sp<SkData> load(const char[], const char[]) const override; |
139 | sk_sp<ImageAsset> loadImageAsset(const char[], const char[], const char[]) const override; |
140 | sk_sp<SkData> loadFont(const char[], const char[]) const override; |
141 | |
142 | private: |
143 | const sk_sp<ResourceProvider> fProxy; |
144 | }; |
145 | |
146 | class CachingResourceProvider final : public ResourceProviderProxyBase { |
147 | public: |
148 | static sk_sp<CachingResourceProvider> Make(sk_sp<ResourceProvider> rp) { |
149 | return rp ? sk_sp<CachingResourceProvider>(new CachingResourceProvider(std::move(rp))) |
150 | : nullptr; |
151 | } |
152 | |
153 | private: |
154 | explicit CachingResourceProvider(sk_sp<ResourceProvider>); |
155 | |
156 | sk_sp<ImageAsset> loadImageAsset(const char[], const char[], const char[]) const override; |
157 | |
158 | mutable SkMutex fMutex; |
159 | mutable SkTHashMap<SkString, sk_sp<ImageAsset>> fImageCache; |
160 | |
161 | using INHERITED = ResourceProviderProxyBase; |
162 | }; |
163 | |
164 | class DataURIResourceProviderProxy final : public ResourceProviderProxyBase { |
165 | public: |
166 | static sk_sp<DataURIResourceProviderProxy> Make(sk_sp<ResourceProvider> rp, |
167 | bool predecode = false); |
168 | |
169 | private: |
170 | DataURIResourceProviderProxy(sk_sp<ResourceProvider>, bool); |
171 | |
172 | sk_sp<ImageAsset> loadImageAsset(const char[], const char[], const char[]) const override; |
173 | |
174 | const bool fPredecode; |
175 | |
176 | using INHERITED = ResourceProviderProxyBase; |
177 | }; |
178 | |
179 | } // namespace skresources |
180 | |
181 | #endif // SkResources_DEFINED |
182 | |